Aging Well: Planning for excessive heat events

Did you know that each year, more people die from "excessive heat events" than from hurricanes, lightning, tornadoes, floods and earthquakes combined?

Anyone can be adversely affected by excessive heat, but older adults are particularly vulnerable. Excessive heat events are prolonged periods when temperatures reach 10 degrees Fahrenheit or more above the average high temperature for a region. Excessive heat events are believed to have a disproportionate public health impact in cities. One reason is roads and buildings absorb the sun's energy and contribute to the formation of "heat islands." While rural areas cool off at night, cities retain this absorbed heat. As a result, urban residents get less nighttime relief from high temperatures.

Fortunately, there are simple steps that older adults, their caregivers and community leaders can take to decrease the impact of excessive heat events.

Who is at risk from extreme heat?

Older adults, as well as young children, are at high risk from excessive heat events. For the growing number of aging Americans, the body's cooling mechanisms may become impaired. Living alone or being confined to a bed and unable to care for one's self further increases risk.

Existing health conditions such as chronic illness, mental impairment and obesity also can heighten an individual's vulnerability. Persons taking certain medications are susceptible.

In addition, people who live on the top floors of buildings without air conditioning are more likely to be exposed to excessive heat. Participating in strenuous outdoor activities and consuming alcohol during unusually hot weather exacerbates heat-related health effects.

How does excessive heat affect the body?

The body normally cools itself by increasing blood flow to the skin and perspiring.

Heat-related illness and mortality occur when the body's temperature control system becomes overloaded. When this happens, perspiring may not be enough. High levels of humidity can make it even harder for the body to cool itself.

How are excessive heat and heat stroke related?

Heat stroke is the most serious health effect of excessive heat events. It is the failure of the body's temperature control system. When the body loses its ability to cool itself, core body temperature rises rapidly. As a result, heat stroke can cause severe and permanent damage to vital organs. Victims can be identified by skin that appears hot, dry and red. Other warning signs are confusion, hallucinations and aggression. If not treated immediately, heat stroke can result in permanent disability or death. The good news is that heat stroke can be prevented by taking the easy steps outlined on this page.

What cost-effective steps can make cool air?

Two steps that communities can take include using construction material that reflect the sun's rays, and planting trees and vegetation to provide shade and natural cooling. Both strategies reduce the urban heat island effect - urban temperatures 2 to 10 degrees Fahrenheit hotter than surrounding rural areas - and may limit the frequency, duration and magnitude of excessive heat events.

Heat reduction strategies such as using reflective "cool roofs" and light-colored pavements, and planting shade trees have numerous benefits.

These measures:

• Lower ambient temperatures

• Slow heat-driven reaction that forms ozone air pollution

• Decrease energy consumption

• Improve comfort and livability

How can I reduce excessive heat exposure?

The best defense against excessive heat is prevention. Air conditioning is one of the best protective factors against heat-related illness and death. Even a few hours a day in air conditioning can greatly reduce the risk. Electric fans may provide comfort, but when temperatures are in the high 90s, fans do not prevent heat-related illness. During excessive heat events, the following prevention strategies can save lives:

• Visit air-conditioned buildings in your community if your home is not air conditioned. These may include senior centers, movie theaters, libraries, shopping malls or designated "cooling centers."

• Take a cool shower or bath.

• Drink lots of fluids. Don't wait until you are thirsty to drink. If a doctor limits your fluid intake, make sure to ask how much to drink when it's hot. Avoid beverages containing caffeine, alcohol or large amounts of sugar. These drinks cause dehydration.

• Ask your doctor or other health care provider if the medications you take could increase your susceptibility to heat-related illness.